DEBT AND CREDIT FACILITIES

The following table summarizes the carrying amount of our borrowings under various financing arrangements (in millions):



				December 31,
Type of Borrowing	Issue Date	Due Date	Interest Rate	2018		2017
Senior Unsecured	September 2015	September 2018	1.85%	$	—	$	999
Senior Unsecured	September 2017	September 2018	3-month LIBOR + 0.17%	—		749
Term Loan	October 2017	October 2018	Variable	—		999
Senior Unsecured	September 2017	March 2019	3-month LIBOR + 0.22%	750		748
Senior Unsecured	March 2014	April 2019	2.05%	500		499
Senior Unsecured	September 2017	September 2019	1.85%	999		997
Senior Unsecured	September 2017	September 2019	3-month LIBOR + 0.25%	499		499
Senior Unsecured	November 2014	February 2020	2.35%	499		499
Senior Unsecured	September 2015	September 2020	2.55%	1,996		1,994
Term Loan	October 2017	October 2020	Variable	—		998
Senior Unsecured	March 2011	April 2021	4.50%	997		995
Senior Unsecured	December 2011	December 2021	4.40%	1,247		1,246
Senior Unsecured	September 2016	March 2022	1.95%	498		497
Senior Unsecured	September 2015	September 2022	3.25%	997		996
Term Loan	October 2017	October 2022	Variable	—		2,497
Senior Unsecured	September 2016	September 2023	2.50%	746		745
Senior Unsecured	March 2014	April 2024	3.70%	1,744		1,742
Senior Unsecured	November 2014	February 2025	3.50%	1,745		1,744
Senior Unsecured	September 2015	March 2026	3.65%	2,731		2,729
Senior Unsecured	September 2016	March 2027	2.95%	1,245		1,244
Senior Unsecured	September 2015	September 2035	4.60%	990		990
Senior Unsecured	September 2016	September 2036	4.00%	740		740
Senior Unsecured	December 2011	December 2041	5.65%	995		995
Senior Unsecured	March 2014	April 2044	4.80%	1,734		1,733
Senior Unsecured	November 2014	February 2045	4.50%	1,730		1,730
Senior Unsecured	September 2015	March 2046	4.75%	2,216		2,215
Senior Unsecured	September 2016	March 2047	4.15%	1,724		1,723
Total debt, net				27,322		33,542
Less current portion				2,748		2,747
Total long-term debt, net				$	24,574	$	30,795

Senior Unsecured Notes

In 2017, in connection with our acquisition of Kite, we issued $3.0 billion aggregate principal amount of senior unsecured notes in a registered offering consisting of $750 million principal amount of floating rate notes due September 2018, $750 million principal amount of floating rate notes due March 2019, and $500 million principal amount of floating rate notes due September 2019 (collectively, the Floating Rate Notes) and $1.0 billion principal amount of 1.85% senior notes due September 2019 (the Fixed Rate Notes, and collectively with the Floating Rate Notes, the 2017 Notes), the terms of which are summarized in the table above. In 2018, we repaid at maturity $750 million of principal balance related to the Floating Rate Notes.

We collectively refer to the 2017 Notes, and our senior unsecured notes issued in September 2016 (the 2016 Notes), in September 2015 (the 2015 Notes), in March and November 2014 (the 2014 Notes) and in March and December 2011 (the 2011 Notes) as our Senior Notes. In 2018, we repaid at maturity $1.0 billion of principal balance related to the 2015 Notes.

Our Senior Notes, except for the Floating Rate Notes, may be redeemed at our option at a redemption price equal to the greater of (i) 100% of the principal amount of the notes to be redeemed and (ii) the sum, as determined by an independent investment banker, of the present values of the remaining scheduled payments of principal and interest on the notes to be redeemed (exclusive of interest accrued to the date of redemption) discounted to the redemption date on a semiannual basis at the Treasury Rate, plus a make-whole premium as defined in the indenture. Our Senior Notes maturing after 2020 also have a call feature, exercisable at our option, to redeem the notes at par in whole or in part one to six months immediately preceding maturity. In each case, accrued and unpaid interest is also required to be redeemed to the date of redemption. We do not have the option to redeem any series of the Floating Rate Notes, in whole or in part, prior to the maturity date.

In the event of the occurrence of a change in control and a downgrade in the rating of our Senior Notes below investment grade by Moody’s Investors Service, Inc. and S&P Global Ratings, the holders may require us to purchase all or a portion of their notes at a price equal to 101% of the aggregate principal amount of the notes repurchased, plus accrued and unpaid interest to the date of repurchase. We are required to comply with certain covenants under our Senior Notes and as of December 31, 2018 and 2017, we were not in violation of any covenants.

Interest expense on our Senior Notes related to the contractual coupon rates and amortization of the debt discount and issuance costs was $1.1 billion, $1.0 billion and $907 million in 2018, 2017 and 2016, respectively.

Term Loan Facilities

In September 2017, we entered into a $6.0 billion aggregate principal amount term loan facility credit agreement consisting of a $1.0 billion principal amount 364-day senior unsecured term loan facility, a $2.5 billion principal amount three-year senior unsecured term loan facility and a $2.5 billion principal amount five-year senior unsecured term loan facility (collectively, the Term Loan Facilities). In October 2017, we drew $6.0 billion principal amount on the Term Loan Facilities and used the proceeds to finance our acquisition of Kite, of which $1.5 billion was repaid in 2017 and the remaining $4.5 billion was repaid in 2018. The term loan facility credit agreement was terminated in 2018.

Credit Facilities

In 2016, we entered into a $2.5 billion five-year revolving credit facility agreement maturing in May 2021 (the Five-Year Revolving Credit Agreement). The revolving credit facility can be used for working capital requirements and for general corporate purposes, including, without limitation, acquisitions. As of December 31, 2018 and 2017, there were no amounts outstanding under the Five-Year Revolving Credit Agreement.

The Five-Year Revolving Credit Agreement contains customary representations, warranties, affirmative and negative covenants and events of default. At December 31, 2018, we were not in violation of any covenants. Loans under the Five-Year Revolving Credit Agreement bear interest at either (i) the Eurodollar Rate plus the Applicable Percentage, or (ii) the Base Rate plus the Applicable Percentage, each as defined in the Five-Year Revolving Credit Agreement. We may terminate or reduce the commitments, and may prepay any loans under the Five-Year Revolving Credit Agreement in whole or in part at any time without premium or penalty.

Contractual Maturities of Financing Obligations

As of December 31, 2018, the aggregate future principal maturities of financing obligations for each of the next five years, based on contractual due dates, are as follows (in millions):



	2019		2020		2021		2022		2023
Contractual Maturities	$	2,750	$	2,500	$	2,250	$	1,500	$	750